Absorption, Translocation, and Activity of Fluazifop-Butyl as Influenced by Plant Growth Stage and Environment

Absorption and translocation of14C-fluazifop-butyl {butyl ester of (±)-2-[4-[[5-(trifluoromethyl)-2-pyridinyl] oxy] phenoxy] propanoate} was compared in susceptible quackgrass [Agropyron repens(L.) Beauv. ♯3AGRRE] and tolerant soybean [Glycine max(L.) Merr.]. Foliar absorption was more rapid in soybeans with 75% of the recovered14C absorbed 6 h after treatment compared to 36% in quackgrass. Translocation of the radiolabel occurred in both soybean and quackgrass with no significant difference between the species. Differential absorption and translocation did not contribute to the selectivity of fluazifop-butyl. Herbicidal activity was lower on quackgrass plants at the five- to six-leaf stage when compared to the two- to three-leaf stage. Greater quackgrass control was observed at 30 than at 20 C. Foliar absorption of14C-fluazifop-butyl was significantly greater at 30 than at 20 C. Translocation of the radiolabel was greater in plants exposed to full light as compared to shade. Moisture stress significantly reduced quackgrass control with fluazifop-butyl.

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Canola Growth Stage at Time of Infection Determines Magnitude of White Leaf Spot (Neopseudocercosporella capsellae) Impact

Plant Disease ◽

10.1094/pdis-09-20-2036-re ◽

2020 ◽

Author(s):

Tamsal Murtza ◽

Ming Pei You ◽

Martin John BARBETTI

Keyword(s):

Plant Growth ◽

Seed Yield ◽

Leaf Spot ◽

Growth Stage ◽

Disease Incidence ◽

Leaf Spot Disease ◽

Leaf Stage ◽

Spot Disease ◽

White Leaf ◽

Field Plots

White leaf spot (Neopseudocercosporella capsellae) is a persistent and increasingly important foliar disease for canola (Brassica napus) across southern Australia. To define the role of plant growth stage on development of the disease epidemic, we first investigated the response of different canola cultivars (Scoop and Charlton) at five Sylvester-Bradley growth stages against N. capsellae. White leaf spot disease incidence and severity was dependent upon plant growth stage and cultivar (both P < 0.001), with plants being most susceptible at plant growth stage 1,00 (cotyledon stage) followed by plant growth stage 1,04 (4th leaf stage). Then, second, to quantify the impact of this disease on canola yield, we investigated the in-field relationship of white leaf spot disease incidence and severity with seed yield loss following artificial inoculation commencing at growth stage 1.04 (4th leaf stage). White leaf spot significantly (P < 0.001) reduced seed yield by 24% in N. capsellae inoculated field plots compared with non-inoculated field plots. We believe that this is the first time that serious seed yield losses from this disease have been quantified in-field. The current study demonstrates that N. capsellae disease incidence and severity on canola is determined by host growth stage at which pathogen infestation occurs. Emerging seedling cotyledons were highly susceptible, followed by less susceptibility in first true leaves to emerge but then increasing susceptibility as plants subsequently age towards the 4th leaf stage. This explains field observances where white leaf spot readily establishes on emerging seedlings and subsequently becomes more prevalent and severe as plants age.

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Control and Seedhead Suppression of Red Rice (Oryza sativa) in Soybeans (Glycine max)

Weed Technology ◽

10.1017/s0890037x00031742 ◽

1989 ◽

Vol 3 (2) ◽

pp. 238-243 ◽

Cited By ~ 6

Author(s):

Frederick P. Salzman ◽

Roy J. Smith ◽

Ronald E. Talbert

Keyword(s):

Oryza Sativa ◽

Soil Moisture ◽

Glycine Max ◽

Plant Growth ◽

Growth Regulators ◽

Moisture Stress ◽

Growth Stages ◽

Red Rice ◽

Soil Moisture Stress ◽

High Soil Moisture

Experiments were conducted in 1985 and 1986 at three locations in eastern Arkansas to evaluate red rice control in soybeans with postemergence grass herbicides and plant growth regulators applied singly or sequentially at early to late-tillering growth stages of red rice. Haloxyfop at 0.21 kg ai/ha and quizalofop at 0.14 kg ai/ha applied singly or sequentially and fluazifop at 0.21 kg ai/ha applied sequentially consistently controlled red rice and suppressed seedhead production in soybeans. Mid-season treatments were not beneficial when high soil moisture stress conditions existed. Mefluidide or sethoxydim applied singly or sequentially or amidochlor applied singly provided erratic control and seedhead suppression of red rice in soybeans.

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Performance of BAS 9052 Applied to Johnsongrass (Sorghum halepense) and Soybeans (Glycine max)

Weed Science ◽

10.1017/s0043174500070752 ◽

1983 ◽

Vol 31 (6) ◽

pp. 796-800 ◽

Cited By ~ 20

Author(s):

E. James Retzinger ◽

R. Larry Rogers ◽

Ronald P. Mowers

Keyword(s):

Glycine Max ◽

Growth Stage ◽

Soybean Seed ◽

Moisture Stress ◽

Sorghum Halepense ◽

Growth Stages ◽

Exponential Equation ◽

Yield Increase ◽

Relationship Of ◽

The Relationship

The performance of BAS 9052 {2-[1-(ethoxyimino)-butyl]-5-[2-(ethylthio)-propyl]-3-hydroxy-2-cyclohexen-1-one} was evaluated when applied postemergence to rhizome and seedling johnsongrass [Sorghum halepense(L.) Pers. # SORHA] in soybeans [Glycine max(L.) Merr. ‘Bragg’ and ‘Centennial’] when the soybeans had four or five trifoliate leaves (V3 to V4 stages) or when they had six to eight trifoliate leaves (V5 to V7 growth stages). The degree of weed control was more strongly associated with rainfall conditions than with the size of the johnsongrass. An exponential equation was used to describe the relationship of soybean seed yield to BAS 9052 rate. BAS 9052 applications of 0.28 kg ai/ha provided an estimated 98% of the potential soybean yield increase when rainfall was adequate but, 0.41 kg ai/ha was required when the plants were grown under moisture stress. Soybean yields were increased by 260 kg/ha when BAS 9052 was applied at the V3 to V4 compared to the V5 to V7 growth stage.

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Efficacy ofColletotrichum coccodesand Thidiazuron for Velvetleaf (Abutilon theophrasti) Control in Soybean (Glycine max)

Weed Technology ◽

10.1017/s0890037x00032292 ◽

1988 ◽

Vol 2 (4) ◽

pp. 473-480 ◽

Cited By ~ 25

Author(s):

Richard H. Hodgson ◽

Lee A. Wymore ◽

Alan K. Watson ◽

Robert H. Snyder ◽

Anne Collette

Keyword(s):

Glycine Max ◽

Plant Growth ◽

Growth Regulator ◽

Plant Growth Regulator ◽

Growth Stage ◽

Pathogenic Fungus ◽

Abutilon Theophrasti ◽

Colletotrichum Coccodes ◽

Growth Stages ◽

Wet Weather

The plant pathogenic fungusColletotrichum coccodes(Cc) and the plant growth regulator thidiazuron (TDZ) were evaluated in Maryland and Quebec for velvetleaf control in ‘Williams' and ‘Maple Arrow’ soybean. TDZ was applied at 0, 0.1, 0.2, 0.3, and 0.4 kg ai/ha alone or was combined with Cc at 109spores/m2when velvetleaf was at the 1- to 2-leaf (Trial 1) or 4- to 6-leaf (Trial 2) growth stages. Velvetleaf control increased with TDZ rate, and TDZ combined with Cc further increased control. TDZ reduced velvetleaf biomass and height, and Cc increased velvetleaf mortality. In Quebec, Cc also reduced the biomass of velvetleaf treated in Trial 1 and interacted positively with TDZ at this growth stage. Cc nearly halved the rates of TDZ required for 90 and 75% mortality of velvetleaf treated at the 1- to 2-leaf and 4- to 6-leaf stages to 0.09 and 0.12 kg/ha, respectively, in Quebec. Cc similarly lowered the rate of TDZ required for 75% stand reduction of velvetleaf in Trial 1 to 0.17 kg/ha in Maryland. Cool wet weather in Quebec contrasted with warm, dry weather in Maryland. Soybean biomass and yield were increased significantly by treatment with TDZ plus Cc in Trial 1 at both locations.

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Glyphosate Can Reduce Glyphosate-resistant Canola Growth After Individual or Sequential Applications

Weed Technology ◽

10.1614/wt-05-062 ◽

2006 ◽

Vol 20 (4) ◽

pp. 825-830 ◽

Cited By ~ 5

Author(s):

Brian S. Schilling ◽

K. Neil Harker ◽

Jane R. King

Keyword(s):

Plant Growth ◽

Leaf Area ◽

Growth And Development ◽

Growth Stage ◽

Growth Parameters ◽

Growth Parameter ◽

Leaf Stage ◽

Greenhouse Experiments ◽

Three Stages ◽

Shoot Weight

Greenhouse experiments were conducted to determine whether multiple applications of glyphosate and time of glyphosate application with regard to the crop's growth stage had a significant effect on the growth and development of glyphosate-resistant canola. Glyphosate was applied as single applications at the two-, four-, or six-leaf stage of canola; as sequential double applications at the two- and four-, two- and six-, and four- and six-leaf stages of canola; and as a triple application at all three stages. Of the plant growth parameters measured, single applications of glyphosate resulted in significant reductions to stem weight and shoot weight compared with nontreated plants, and multiple applications of glyphosate caused significant reductions to leaf area, leaf weight, stem weight, and shoot weight. Single applications of glyphosate were less injurious to glyphosate-resistant canola compared with multiple applications, and canola growth parameter reductions were greatest after earlier glyphosate applications.

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Dithiopyr Behavior in Smooth Crabgrass (Digitaria ischaemum) as Influenced by Growth Stage and Temperature

Weed Science ◽

10.1614/ws-d-13-00089.1 ◽

2014 ◽

Vol 62 (1) ◽

pp. 11-21 ◽

Cited By ~ 5

Author(s):

Patrick E. McCullough ◽

Diego Gómez de Barreda ◽

Sudeep Sidhu ◽

Jialin Yu

Keyword(s):

High Temperatures ◽

Low Temperatures ◽

Growth Stage ◽

Specific Radioactivity ◽

Growth Stages ◽

Differential Absorption ◽

Treatment Results ◽

Foliar Absorption ◽

Greenhouse Experiments ◽

Temperature And Growth

Dithiopyr provides PRE and early POST control of smooth crabgrass, but POST efficacy is often inconsistent on tillered plants. Experiments were conducted to evaluate the interaction of temperature and growth stage on dithiopyr efficacy, absorption, translocation, and metabolism in smooth crabgrass. In greenhouse experiments, I50(predicted rate to induce 50% injury) measured < 0.14, 0.14, and 0.15 kg ha−1at low temperatures (average 23 C) for multi-leaf, one-tiller, and multi-tiller smooth crabgrass, respectively, while I50measured < 0.14, 0.88, and > 2.24 kg ha−1at high temperatures (average 32 C), respectively. Multi-tiller (three to five tillers) smooth crabgrass absorbed more root applied14C-dithiopyr than multi-leaf (three to four leaves) and one-tiller plants, but specific radioactivity (Bq mg−1) was two to three times greater in multi-leaf plants compared to tillered plants. Smooth crabgrass treated at 15/10 C (day/night) had ≈ two times greater specific radioactivity following root applied14C-dithiopyr than at 30/25 C. Radioactivity distribution to shoots from root applications measured 43, 30, and 20% of the total absorbed for multi-leaf, one-tiller, and multi-tiller plants, respectively. Smooth crabgrass had two times more foliar absorption of14C-dithiopyr at 15/10 than 30/25 C while14C losses were greater at 30/25 than 15/10 C. Smooth crabgrass metabolism of14C-dithiopyr was ≈ two times greater at 30/25 than 15/10 C, and multi-leaf plants averaged 10 to 20% more metabolism than tillered plants at 7 d after treatment. Results suggest differential absorption, translocation, and metabolism may contribute to dithiopyr efficacy on smooth crabgrass at various growth stages, but use under high temperatures (30/25 C) could increase losses from volatilization, reduce foliar absorption, and increase metabolism compared to cooler temperatures (15/10 C).

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Control of Cowpea (Vigna unguiculata) in Soybean (Glycine max) with Acifluorfen

Weed Science ◽

10.1017/s0043174500059270 ◽

1984 ◽

Vol 32 (4) ◽

pp. 427-431 ◽

Cited By ~ 6

Author(s):

Tim R. Murphy ◽

Billy J. Gossett

Keyword(s):

Glycine Max ◽

Plant Growth ◽

Vigna Unguiculata ◽

Single Application ◽

Leaf Stage ◽

Cowpea Cultivars ◽

Nitrobenzoic Acid ◽

Seed Yields ◽

Cowpea Plant

Acifluorfen {5-[2-chloro-4-(trifluoromethyl)phenoxy]-2-nitrobenzoic acid} applied 7 days after cowpea [Vigna unguiculata(L.) Walp.] emergence (unifoliolate leaf stage) gave better control than later applications. Cowpea control was obtained with one acifluorfen application at 7 days after cowpea emergence in 1981, but in 1980 and 1982, applications at 7 and 14 days were necessary for acceptable control (> 80%). Acifluorfen reduced cowpea plant dry weights relative to the weedy control. A single application 7 days after emergence reduced cowpea plant growth more than one at 21 days after emergence. Of all times of application, the greatest soybean [Glycine max(L.) Merr.] injury occurred when acifluorfen was applied at 7, 14, and 21 days after emergence, but seed yields were not reduced relative to the untreated weed-free control. There was no difference in response among three weedy cowpea cultivars to acifluorfen.

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Effect of Growth Stage and Environment on Foliar Absorption, Translocation, Metabolism, and Activity of Nicosulfuron in Quackgrass (Elytrigia repens)

Weed Science ◽

10.1017/s0043174500094170 ◽

1996 ◽

Vol 44 (3) ◽

pp. 447-454 ◽

Cited By ~ 15

Author(s):

Joseph A. Bruce ◽

J. Boyd Carey ◽

Donald Penner ◽

James J. Kells

Keyword(s):

Soil Moisture ◽

Air Temperature ◽

Growth Stage ◽

Moisture Stress ◽

Foliar Absorption ◽

Elytrigia Repens ◽

Urea Ammonium Nitrate ◽

Plant Moisture ◽

Moisture Conditions ◽

Petroleum Oil

Experiments were conducted to examine the influence of adjuvant, growth stage, air temperature, and soil moisture on nicosulfuron activity, absorption, and distribution in quackgrass. Foliar absorption of14C-nicosulfuron by quackgrass was greater in one-leaf than five-leaf plants. Total translocation of14C-nicosulfuron was similar regardless of growth stage. However, nicosulfuron was more phytotoxic to three- and five-leaf than one-leaf quackgrass. Of the absorbed14C, at least 71 % remained as14C-nicosulfuron 168 h after application in three-leaf plants.14C-Nicosulfuron absorption, translocation, and accumulation increased with increasing temperatures and was independent of soil moisture. Under adequate soil moisture conditions (-0.03 MPa), nicosulfuron activity was not influenced by temperature. Nicosulfuron efficacy was not influenced by soil moisture at a cool (11/6 C) temperature. As plant moisture stress increased, due to low soil moisture and increasing air temperature, nicosulfuron efficacy declined. Differences in nicosulfuron efficacy due to growth stage or environmental conditions could not be explained by differential14C recovery, absorption, translocation, or accumulation. The addition of 28% urea-ammonium nitrate liquid fertilizer (UAN) to14C-nico-sulfuron plus petroleum oil adjuvant (POA) provided greater14C absorption than POA alone. Translocation of14C with POA alone 168 h after treatment (HAT) was similar to POA plus UAN 24 HAT. However, 168 HAT there was no difference in the total amount of radiolabelled material translocated among the adjuvants.

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Stand Reduction and Foliage Damage Reduce Yield of Dehydrating Onion

HortScience ◽

10.21273/hortsci.39.5.1005 ◽

2004 ◽

Vol 39 (5) ◽

pp. 1005-1007 ◽

Cited By ~ 1

Author(s):

George H. Clough

Keyword(s):

Plant Growth ◽

Growth Stage ◽

Leaf Growth ◽

Field Trials ◽

Growth Stages ◽

Leaf Stage ◽

Plant Growth Stages ◽

The Impact ◽

Stage Yield ◽

Different Growth Stages

Field trials were conducted at Hermiston, Ore., from 1995 through 1998, to determine impact of stand loss and plant damage at different growth stages on yield of onions (Allium cepa) grown for dehydration. Stand reduction (0%, 20%, 40%, 60%, 80%) and foliage damage (0%, 25%, 50%, 75%, 100%) treatments were applied at three-, six-, nine-, and twelve-leaf onion growth stages. Although average bulb weight increased as stand was reduced, marketable, cull, and total yields decreased as stand reduction increased (plant population decreased) at all plant growth stages. Bulb weight was not changed by up to 100% foliage removal at the three-leaf stage. At the six- and twelve-leaf stages, weight was reduced when ≥50% of the foliage was removed. The most severe response occurred at the nine-leaf stage. At the three-leaf stage, yield was not affected by foliage damage. At the six-leaf growth stage, yield was reduced by 75% or more foliage loss, but at the nine- and twelve-leaf stages, ≥50% foliage removal reduced expected yields. As with bulb weight, the impact of foliage removal on yield was most severe at the nine-leaf growth stage.

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Tolerance of Greenhouse-grown Strawberries to Terbacil as Influenced by Cultivar, Plant Growth Stage, Application Rate, Application Site and Simulated Postapplication Irrigation

HortTechnology ◽

10.21273/horttech.14.2.0223 ◽

2004 ◽

Vol 14 (2) ◽

pp. 223-229 ◽

Cited By ~ 1

Author(s):

Steven B. Polter ◽

Douglas Doohan ◽

Joseph C. Scheerens

Keyword(s):

Plant Growth ◽

Growth Stage ◽

Application Rate ◽

Application Site ◽

Leaf Injury ◽

Leaf Stage ◽

Final Experiment ◽

Leaf Emergence ◽

Water Rinse

Terbacil at 0, 0.8, 1.6, 3.2, and 6.4 oz/acre (0, 0.06, 0.11, 0.22, and 0.45 kg·ha-1) a.i. was applied immediately after planting, at the thee-leaf stage and at the six-leaf stage to greenhouse grown strawberry (Fragaria × ananassa) cultivars Jewel, Mira, and Allstar. Strawberry was most tolerant of terbacil when the herbicide was applied before leaf emergence. `Mira' was more tolerant of terbacil than was `Jewel'. `Jewel' and `Allstar' exhibited similar levels of tolerance. In a second experiment terbacil at 4.8 oz/acre (0.34 kg·ha-1) was applied to the soil, to the foliage, and to the foliage followed by a water rinse. Injury was greatest when terbacil was applied directly to the strawberry foliage rather than to the soil, but was minimal when foliage was rinsed after application. In a final experiment terbacil at 4.8 oz/acre was applied to greenhouse-grown `Jewel' strawberries at the thee-leaf stage followed by a water rinse 0.5, 1, 2, or 4 hours after application. Rinsing the foliage of strawberry plants after application significantly reduced leaf injury. Delaying the rinse up to 4 hours did not lead to increased injury. Over all, the results from our study indicate the potential for using terbacil as an effective herbicide on newly established strawberries, especially if the compound is rinsed from leaves (if present) after treatment.

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